Vehicle operator warning systems that alert vehicle operator of objects that may be a collision hazard are known. These systems typically provide the operator an audio and/or visual warning of an impending or potential collision, preferably with sufficient reaction time for the vehicle operator to respond to the warning and make appropriate countermeasures to prevent the collision.
Rear view camera systems that allow the operator to view areas behind the vehicle are also known. These systems help the operator to detect objects blocked from view by the rear portion of the vehicle, or are located in areas commonly known as blind spots. However, even if the vehicle is equipped with a rear view camera system, the operator may not be able to discern potential obstacles displayed by the system. For example, the wide range of ambient lighting conditions experienced by the vehicle, combined with the wide range of reflectivity values of potential objects can make object identification and or classification difficult.
Thermal imaging cameras or infrared cameras have also been used in automotive applications for object detection. However, such cameras have undesirably high cost. Also, some operators have difficulty interpreting what is being indicated in the thermal image as they often resemble an antiquated black and white television display.